Date of Award
Master of Science in Engineering
Electrical and Computer Engineering
Dr. Massood Z. Atashbar
Dr. Bradley J. Bazuin
Dr. Paul D. Fleming
Raman spectroscopy, cocaine detection, optical sensor, illicit drugs detection, gravure printing technology
Masters Thesis-Open Access
In this thesis, the author focuses on the design and fabrication of a novel surface enhanced Raman spectroscopy (SERS) substrate that could potentially be employed for the detection of illicit drugs. Raman spectroscopy based optical detection has been extensively employed as a qualitative and quantitative analytical method.
The author has worked on two research projects, which are both focused on the development of printed SERS substrate for the detection of cocaine. The first project is based on gravure printing of silver nanoparticle (AgNP) based ink on flexible and stretchable thermoplastic polyurethane (TPU) substrate. The fabricated substrate dimensions are 1.5 × 1.5 inches, and the average thickness and roughness for the printed AgNP film was measured to be 7.78 μm and 0.18 μm, respectively. An enhancement factor (EF) of three, in the intensity of Raman signal of cocaine on the printed SERS substrate, was observed when compared to target molecules absorbed on a bare TPU substrate. This EF is based on the large electromagnetic fields, created by interaction of the AgNPs with light.
The second project is focused on the fabrication of a rougher surface of the SERS substrate to amplify the generated electromagnetic fields that could result in a larger enhancement of the Raman signal intensity. The SERS substrate was designed with dimensions of 3 × 0.5 inches, and was fabricated by gravure printing the AgNP ink on a stretched (25%, 50%, 75% and 100%) TPU substrate to form a wrinkled nanostructure SERS surface. An EF of 2, in the intensity of Raman peak of cocaine for the 25% stretched SERS substrate with an average roughness of 1.57 μm was observed, when compared to the Raman signal of cocaine on the non-stretched SERS substrate. And an EF of 6, in the intensity of Raman spectra of cocaine for the 25% stretched SERS substrate when compared to the Raman spectra of cocaine on the bare TPU substrate.
Aljanabi, "Development of a Novel Printed and Flexible Surface Enhanced Raman Specopy (Sers) Substrate for Detection of Cocaine" (2017). Master's Theses. 1518.